\documentclass{standalone}
\usepackage{tikz}
\usepackage{ctex,siunitx}
\setCJKmainfont{Noto Serif CJK SC}
\usepackage{tkz-euclide}
\usepackage{amsmath}
\usetikzlibrary{patterns, calc}
\usetikzlibrary {decorations.pathmorphing, decorations.pathreplacing, decorations.shapes,}
\begin{document}
\small
\begin{tikzpicture}[>=latex,scale=1]
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  \fill [pattern = north east lines] (0,-0.5) rectangle (5,-.25);
  \draw [thick](0,-0.25)--(5,-0.25);
  \draw[->,thick] (2.6,1.3/2)--(2.6, 1.3/2+1.5)node[right]{$N$};
  \fill (2.6,1.3/2) circle[radius=1.5pt];
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  ;
\end{tikzpicture}
\end{document}